1. Technical Field
This invention relates generally to mixers, and more specifically, to in-line mixers without moving parts. The mixer of this invention provides intense shearing and mixing forces from the energy of fluid mixtures passing through it and around it to provide stable, well-distributed dispersions, without the need for moving parts and without the entrainment of air into the dispersions.
2. Background Art
U.S. Pat. No. 3,744,763 (Schnoring et al.) discloses a homogenizing machine with a rotor, an end face of which has rings formed with recesses. The rotor rings revolve between similar rings arranged on the inside of the rotor housing to help create shearing and mixing forces and an emulsion therein.
U.S. Pat. No. 4,333,729 (Marugg) discloses a homogenizing unit with a conical bore hole and a conical plunger, the plunger having successive ring-shaped steps on it.
U.S. Pat. No. 4,909,635 (Lecoffre et al.) discloses a homogenizing machine with a perforated tubular insert having a solid diagonal baffle as a flow director in its center.
U.S. Pat. No. 4,944,602 (Buschelburger) discloses a homogenizing machine with a nozzle, a cutting edge between the inlet and the outlet, and downstream of the cutting edge, a circumferential recess. The mixture in the machine is subjected to an acceleration zone at the cutting edge, and a micro-turbulence zone in the circumferential recess.
Still, there is a need for an in-line mixer for dispersions which is of simple and inexpensive construction, without moving parts, and which operates without introducing air or gas bubbles into the dispersion.